Bad AC Compressor sensor

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M

Mxndrnks

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Bad AC Compressor sensor - fixed

Hi all,

I have been looking through the old post about AC problems and I am not finding this exact one. So, if it is out there and you can link me to it that would be super!

So, my AC stopped working a couple of weeks ago. I took it to the shop this morning to get Smogged and asked the shop to look at it. They called me and told me the compressor lock sensor is bad. They said unfortunately the sensor is built into the Compressor and to fix it would cost either almost $1200 for a new compressor and labor to install or around $275 to bypass the sensor. At first the $275 solution seems like a no brainer. But, if the compressor should seize up, then what would be the thing to worry about? Blown belt? Other?

Any one else been through this? Have a link to a compressor replacement that isnt going to cost the farm? Any one replaced the built in sensor? Looking for some advice here.

Thanks!
 
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OK.... Well who on here has replaced the Compressor themselves? I was looking in the FSM and other than the pain in the backside of having to pull the LH driveshaft, any tricky things I should know about?

What about draining the refrigerant? Any one done that or have any tips? It is been almost 15 years since I have worked on AC&R systems and then it was on a ship in the Navy. Looks like I can get a compressor for 3-400 bones and recharging the system will run around $150-175. So I can save $5-600 if I do most of it myself.

Thanks again!
 
hi, my got the same problem. there is no way you can change the sensor only. the solution is change the compressor. i just replaced my compressor with a used one below equivalent $200 us dollars and its working ok.

check from other source for the compressor which will not cost that $1200. ofcourse you have to recharge the gas.

for everything-change compressor, condenser and gas refilling cost me below $500 dollars though items are brought out from a used landcruiser that has engine problem.
 
I expect you are talking about the magnetic clutch sensor?
From the wiring diagram it appears that it sends a "ground input" signal to the ECU when the clutch is engaged, from what I've read it is a speed pulse, but it may be possible to bypass as previously mentioned. It appears to shut the A/C down when there is a discrepancy in the engine speed and the compressor speed (slipping belts).
You may be able to switch an engine speed pulse to the A/C ECU with a relay powered by the magnetic clutch.
EDIT: You may need a separate speed pulse as it appears the crankshaft sensor powers the engine ECU and it appears we want a ground switched circuit
 
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Update AC working:

Fixed the AC. Using the FSM I went into trouble shooting mode. I started with the AC diagnostics. First code I got was for a bad Solar sensor. While trying to test it to see if it was bad I definately broke it... then droped it down inside the dash behind the instrument cluster.... Crap! So, I called CDan to order a new one. In the mean time I moved on to testing the magnetic clutch relay. That made no difference. I was really hoping it would be that simple. So, I went ahead and spent the money on a pretty good Fluke meter and tested the sensor on the compressor. Maybe I dont really know how to use my meter that well because the reading I got were out of spec according to the manual. I am fairly new with working electrical systems. However, I worked on engines and subsystems for years in the Navy.

So, Last Thursday I went ahead and ordered a new compressor knowing I would need to get it fixed this week before I take my wife and 19mo old on an offroad camping trip next weekend.

So, Friday the new Solar Sensor arrived. I had to take apart the instrument panel to find the old sensor and fish it back through the hole in the dash. It was a total pain in the rear!!!!! But, I got the sensor changed out. Start up the car, turn on the AC.... everything is working perfect! I cant believe it. The part only cost $30.

Sort of really disappointed in the shop that diagnosed and said I needed a new compressor. We ahve gone there for years and they have always been on the level. But, they are not toyota specialist. I will definately go to another shop from now on that is more toyota specific but still not a dealer. I hope this helps some one else down the road that has been told they need to replace the compressor.

I will hold onto the compressor I just purchased for a couple of weeks to make sure everything keeps working. The readings I was pulling on the Fluke still have me a little curious if it was just me not doing things right... or if the compressor is really going bad.

Cheers.
 
Good info Mxn. Glad to see you got it fixed and thanks for the update. I'll bet a good 50% of these common problem threads on mud are never posted with the resolution.

:beer:
 
Seeing how you have a new compressor can you take a reading from it then again from yours? Verify you are doing it correctly.


Mxndrnks said:
Update AC working:

Fixed the AC. Using the FSM I went into trouble shooting mode. I started with the AC diagnostics. First code I got was for a bad Solar sensor. While trying to test it to see if it was bad I definately broke it... then droped it down inside the dash behind the instrument cluster.... ****! So, I called CDan to order a new one. In the mean time I moved on to testing the magnetic clutch relay. That made no difference. I was really hoping it would be that simple. So, I went ahead and spent the money on a pretty good Fluke meter and tested the sensor on the compressor. Maybe I dont really know how to use my meter that well because the reading I got were out of spec according to the manual. I am fairly new with working electrical systems. However, I worked on engines and subsystems for years in the Navy.

So, Last Thursday I went ahead and ordered a new compressor knowing I would need to get it fixed this week before I take my wife and 19mo old on an offroad camping trip next weekend.

So, Friday the new Solar Sensor arrived. I had to take apart the instrument panel to find the old sensor and fish it back through the hole in the dash. It was a total pain in the rear!!!!! But, I got the sensor changed out. Start up the car, turn on the AC.... everything is working perfect! I cant believe it. The part only cost $30.

Sort of really disappointed in the shop that diagnosed and said I needed a new compressor. We ahve gone there for years and they have always been on the level. But, they are not toyota specialist. I will definately go to another shop from now on that is more toyota specific but still not a dealer. I hope this helps some one else down the road that has been told they need to replace the compressor.

I will hold onto the compressor I just purchased for a couple of weeks to make sure everything keeps working. The readings I was pulling on the Fluke still have me a little curious if it was just me not doing things right... or if the compressor is really going bad.

Cheers.
Click to expand...
 
I have the same kind of trouble and fsm trouble shooting drove me to a compressor sensor replacement...
But, I find this weird, because if I shunt the MG clutch relay to have the compressor running, it runs... but no cold air...
If I corectly understand what 100TD wrote, with a bad compressor sensor sensor, the compressor would run and then stop, wich is not my case.
I also wanted to test the solar sensor and also broke it, without having it fallen behind the dash... the new sensor cost me 65$ cad... ouch, and still not working
 
OursSauvage said:
But, I find this weird, because if I shunt the MG clutch relay to have the compressor running, it runs... but no cold air...
Click to expand...
If you manually run the compressor by powering the clutch and you get no cold air then I expect you are out of gas. Check the low pressure switch.
 
that's the next step, checking this switch and have a refill.
Thanks for the advice
 
Back from a (non toyota) mechanics... the line to the rear is leaking all way long (each connection, as he said)
I now have to find the price...:frown:
 
Reviving this thread:)

My AC stopped working.

I pulled a vacuum for 40 minutes.

Added 3 12 oz cans of refrigerant.

100 psi on both low and high side. The compressor clutch is not engaging.

How do I by pass the pressure switch? Which Electrical plug do I remove off the compressor to short? I see two of them.

Does this make the AC run 100% of the time?
 
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